Dryer felt



Sept. 30, 1958 J. R. L. SANTOS DRYER FELT 4 Sheets-Sheet 1 Filed Aug. 20. 1953 INVENTOR. JOHN R. L. SANTOS P 30, 1958 J. R. L. SANTOS 2,854,032

DRYER FELT Filed Aug. 20. 1953 4 Sheets-Sheet 2 IN V E1! TOR.

JOHN R. L. SANTOS P 1958 J. R. SANTOS 2,854,032

DRYER FELT Filed Aug. 20. 1953 4 Sheets-Sheet 3 L73 EH50 59 IN VEN TOR.

JOHN R.L. SANTOS P 1958 J. R. L. SANTOS 2,854,032

DRYER FELT Filed Aug. 20. 1953 4 Sheets-Sheet 4 FIG. IO

IN V EN TOR.

J9HN R. L. SANTOS United States Patent DRYER FELT John R. L. Santos, Baltimore, Md., assignor to William E.

Hooper and Sons Company, Baltimore, Md, a corporation of Maryland Application August 20, 1953, Serial No. 375,387

7 Claims. (Cl. 139-411) The present invention relates to a dryer felt primarily for use in the paper making industry in which the paper is dried while on the felt by passing the felt between heated rollers.

Such felts are at times 300 inches wide and of very considerable length, so that lengthwise as well as crosswise they must be quite strong. They have usually been made of cotton or other vegetable fibers to give the required strength, but when they are subjected to high temperature when wet, they rapidly scorch and rot and because of this destruction they have frequently been made partly of asbestos or similar heat and acid resistant materials, retaining a large proportion of warp ends of cotton to assure the required strength.

The desirability of two types of warp ends has frequently been met by the use of two plies of filling, and frequently two plies of filling and warp ends making complete plies, and it is one object of this invention, using two plies of filling, but not two distinct plies of filling and warp ends, to completely cover the top of the feltwith one material, such as asbestos forming the face warps and not to have any of that material in the bottom ply, thus making a felt which is primarily heat resistant and non-absorbent on the top, and strong throughout. The strands which constitute each face appear only on that face.

Another object of the invention is to cover the filling with the asbestos or face warps, and this is accomplished by two face warps together passing over every upper ply filling, while only one passes directly under such filling, thus causing the face warps, when crowded together, to cover the upper filling.

Another object is to make the face of the felt substantially a continuous surface to smoothly support the paper, and the bottom is quite open to allow the maximum drainage through the entire felt.

The excessive use of asbestos has heretofore increased weight and expense, with corresponding loss of strength, and another object of this invention is to substantially lower the quantity of asbestos used by making substantially all the back warps of cotton, so that, in a multiply felt, the asbestos warps need not exceed fifty percent of the warp ends.

To accomplish the above objects, in the preferred structure, each asbestos or face warp will bind two adjacent fillings, and the back warps, where they cross the upper ply of fillings, will be covered by asbestos face warps.

While several objects of the invention have been specifically set forth, there are also other objects and advantages included in its novel construction, which will become apparent as the nature of the invention is more fully disclosed in the following drawingsiand described in the detailed description to follow in which:

Figure 1 is a longitudinal sectional view of a felt having two filling plies taken along line 11 of Figure 2, looking in the direction of the arrow, showing three asbestos warps, three cot-ton warps and two plies or rows of cotton wefts, or filling strands.

Figure 2 is a top plan of the felt, showing only the asbestos warps and the filling in the face or uppermost ply, the warp and weft filling strands being spaced apart for convenience in illustration.

Figure 3 is a longitudinal sectional view taken along line 11 of Figure 2, looking in the direction of the arrow, showing the manner in which a single asbestos warp is superimposed upon a back warp, including the relative location of the filling in respect to the asbestos face warp and a corresponding back warp.

Figure 4 is a sectional view similar to Figure 1 taken along line 44 of Figure 5.

Figure 5 is a view similar to Figure 2 of a modified form of weave for the felt.

Figure 6 is a sectional view similar to Figure 3 taken along line 4--4 of Figure 5 looking in the direction of the arrow.

Figure 7 is a sectional view taken along line 7-7 of Figure 8, looking in the direction of the arrow.

Figure 8 is a view similar to Figure 2 of another modified form of weave for the felt.

Figure 9 is a sectional view taken along line 7-7 of Figure 3, looking in the direction of the arrow, similar to Figure 3.

Figure 10 is a sectional view similar to Figure 1 of a fabric having three filling plies taken alongline Ill-10 of Figure 12, looking in the direction of the arrow, showing two facing asbestos warps and four back cotton warps.

Figure 11 is a sectional view taken along line 11-11 'of Figure 12, looking in the direction of the arrow.

In referring to the drawings similar reference char- V acters are used to indicate the same or similar parts in the different figures.

The figures are drawn to an enlarged scale and are largely diagrammatic in nature. Also for the purpose of the description the surface of the felt carrying the asbestos strands will be referred to as the face, or top of the felt, while the opposite side will be referred to as the back or bottom side of the felt.

Referring first in particular to Figures 1, 2 and 3 the weave pattern of the felt is shown made up of warp.

strands 1, 2, 3, 4, 5, 6, 7, 8 and 9. Warps 4 to 9 are facing warps of asbestos and are so woven into the fabric as to cover the complete face of the material, while back warps 1, 2 and 3, are in this instance cotton and make up the central and back portions of the felt, connecting the filling plies together and at the same time providing strength to the felt. The asbestos strands 7, 8 and 9 in Figure 2 are shown for the purpose of showing the continuation of the weave pattern. The wefts are in two plies, one adjacent the face as illustrated by numerals 10 to 18 and the other adjacent the back, illustrated by numerals 19 to 27. Each row of filling has the same number of strands, arranged one above the other in a plane normal to the parallel face and back of the felt. Referring now in particular to Figure 2, there is shown the plan view of the face or asbestos warps 4, 5 and 6 and 7, 8 and 9 illustrating the continuation of the weave pattern, a single set of warps consists of the three face asbestos strands 4, 5 and 6 and three back cotton warps 1, 2 and.3. In describing the details of the weave, it will be noted that the face asbestos warp 4,

Patented Sept. 30, 1958 13 and 14 under weft 15, over wefts 16 and 17, and under wefts 18. Face warp 6 extends under weft 10, over wefts 11 and 12, under weft 13, over wefts 14 and 15, under weft 16 and over wefts 17 and 18.

Extending under each of the facing asbestos strands are back cotton warps, 1, 2 and 3' which may hereinafter be referred to as companion strands. The facing asbestos warps are comparatively fluffy and of lesser tensile strength in comparison to the cotton warps, and each asbestos warp overlies a companion cotton warp 1, 2 or 3. When the warps are tightly pressed together in the weaving process, the asbestos strands spread out to cover the complete surface of the face of the felt. The back warps engage both plies, the top and bottom rows of the weft or filling and carry substantially the full load of the material.

Referring now in particular to the weaving of the back warps, 1, 2 and 3 the warp 1 is shown beginning at the right extending over weft 10 in the top row, under weft 20 in the lower row, over wefts 12 and 13 in the top row, under weft 23 in the lower row, over wefts l5 and 16 in the top row, under weft 26 in the lower row and over weft 18 in the top row. The back warp. 2, beginning from the right, overlies wefts and 11 in the top row, and passes under weft 2.1 in the lower row, over wefts 13 and 14 in the top row, under weft 24 in the lower row, over wefts 16 and 17 in the top row, and. under weft 27 in the lower row, and underlies asbestos strand 5. The back warp 3, begining from the right, extends under weft 19 in the lower row, over wefts 11 and 12 in the top row, under weft 22 in the lower row, over wefts 14 and in the top row, under weft 25 in the lower row and over wefts 17 and 18 in the top row and underlies the asbestos warp 6.

The relative location of the asbestos warp and its companion back warp in the finished weave is clearly shown in Figure 3.

It will be noted that the asbestos warp does not engage any of the wefts 19 to 27 in the lower ply, but only engages the wefts in the upper row and that each asbestos warp extends over two wefts and then under one.

Referring now to Figures 4, 5 and 6, this felt is also composed of three facing asbestos and three back warps and two transverse rows of weft or filling to make up. a two ply felt. The facing warps of one set are numbered 28, 29 and 3t), and each passes over two wefts and then under one. Two sets of facing warps are illustrated, the others being numbered 31, 32 and 33. To each set of facing warps there is a set of back warps, 34, 35 and 36, and under each facing warp is a back warp, as shown in Figure 6. Each ply is composed of an upper layer of filling, 37, 38, 39, 40, 41, 42 and 43, reading from the right in the figures. The lower ply filling wefts are numbered 44, 45, 46, 47, 48, 49, S0 and 51, all as shown. In this modification the top filling wefts are midway between each two lower wefts.

In describing this form of weave the facing asbestos warp 28 extends under wefts 37, 40, and 43, and over wefts 38, 39, 41 and 42 in the upper ply. The facing asbestos warp '29 extends under wefts 38 and 41 and over wefts 37, 39, 40, 42 and 43 and asbestos warp 30 extends under wefts 39 and 42 and over wefts 37, 38, 40, 41 and 43.

The back warps engage every third weft in both the top and bottom rows of the filling. It will be noted in Figure 6, showing only two warps, the facing asbestos warp 28 and the back warp 34, that the back warp 34 does not extend over two consecutive top wefts as does warp 1 in Figure 3.

In this modification also, two facing warps next to each other cover every weft beneath which a single facing warp extends, the two expanding laterally and covering the wefts when the strands are packed together.

A further form of the invention is illustrated in Figures- 4 7, 8 and 9'. It will be noted that the facing asbestos warps have substantially the. same relation to the upper ply wefts as they have in Figures 4, 5 and 6. The back warps are in reverse to the weave shown in Figures 1, 2 and 3. A simple illustration of this is shown in Figure 9, showing a single facing asbestos warp 52 and the companion back warp 58, in which the back warp 58 is shown extending over wefts 62, 65 and 68 in the upper row of filling and under wefts 72, 73, 75, 76, 73 and 79 in the lower row of filling. That is, the warp 58 engages one weft in the upper row and passes under two wefts in the lower row and again passes over one weft in the top row, throughout the length of the felt. The other two back warps of the set pick up the other two filling wefts in succession, for example Warp 59 extends over wefts 63, 66 and 69 in the top row and pass down and under wefts 73, 74, 76, 77 and 79 in the lower row. Warp 60 extends over wefts 64, 67 and 70 in'the top row and under wefts 71, 72, 74, 75, 77 and 78' in the lower row. Here again the facing asbestos warps overlie the back warps.

In this modification also, two facing warps next to each other cover every weft beneath which a single adjacent facing Warp extends, the two expanding laterally and covering the wefts when the strands are packed together.

A still further modification of the improved invention is shown in Figures 10, 11, 12 and 13. In this form only two facing asbestos warps are used, and there are four backwarps which all together make up a set in the weave. In Figure 13 there is shown facing asbestos warp 80, a back warp 82 underlying the facing asbestos warp and a lower back warp 83. In Figure 10 there is shown the facing asbestos warp 81 and an underlying back Warp 84 and a lower back warp 85. The combination of these two illustrations is shown in Figure 11, and it will be noted that in this form the ratio of back to facing warps is two-to-one. It will also be noted that in this form the filling wefts are arranged in three rows or plies, a top row and a bottom row of an even number of strands arranged one above the other as described for Figures 1, 2 and 3 and an intermediate row located in the center, midway the interval of and between the top and bottom rows of wefts; Referring again briefly to Figure 13 the facing asbestos warps extend under weft 91, and over wefts 86, 87, 88"and 89 in the top row. Immediately underlying the facing asbestos warp is the upper back warp 82 extending likewise under weft 91, but only over wefts 86 and 88 of the top row. Adjacent and alongside the companion back warp 82, is a lower back warp 83 which is interposed longitudinally between the several facing asbestos and their underlying companion back warps. As shown in Figure 10, the back warp 84 and the facing asbestos warp 81 are placed in substantially the same relationship as shown in Figure 13 for the facing asbestos warp and the upper back warp 82, after which a secend lower back warp 85 is shown between the combination facing asbestos warp 81 and its companion upper back warp 84 and the next facing asbestos warp and upper back warp combination, all of which set up a weave pattern of six threads, two facing asbestos warps and four back warps.

Figure l1 shows the complete set of warps, as previously described for each of the facing asbestos warps and the back warps as shown in Figures 10, 12 and 13. As shown clearly in Figure 11, the two lower back warps 83 and 85 pass alternately over and under adjacent wefts in the lower and intermediate rows, the latter being indicated at 90, 91 and 92, uniting them together, while the upper back warps unite the upper and intermediate wefts together according to the pattern described.

In this last modification two facing warps next to each other in each set in the top ply cover every top weft, the two expanding laterally and covering the weft when the strands are packed together.

It will be noted that the facing asbestos warps extend above the upper back warps in all forms of the weave to construct a felt having a face completely covered by the facing warps, and a relatively open back. This construction produces a felt in which the strength is greatly increased in proportion to its weight, and in which the facing warps are firmly held and subjected to substantially no strain.

Now that the purposes and advantages of the weave of the invention have been fully described and clearly illustrated, what is claimed as new and is desired to be secured by Letters Patent is:

1-. A multi-ply woven felt having two or more plies of filling wefts running transversely of the felt and a plurality of warps extending longitudinally of the felt arranged in sets of facing and back warps comprising the weave pattern at least one-third of the total number of warp strands of each set constituting facing warps, the facing warps passing downwardly from the top of the felt substantially through one-half the thickness of the felt and extending alternately over two filling wefts in the top ply and under one weft, the back warps being interwoven to unite all the plies of the filling wefts together, each back warp uniting the top ply filling weft being covered by a facing warp and the back warps include at least three strands for each set comprising the weave pattern.

2. The felt of claim 1 in which the facing warps include a plurality of strands for each set comprising the weave pattern.

3. The multi-ply woven felt as claimed in claim 1 and having two plies of filling wefts running transversely of the felt positioned one above the other and a plurality of warps extending longitudinally of the felt and in which one-half of the total number of warp strands of each set constitute facing warps, the facing warps being interwoven only with the wefts of the upper ply, the remaining warps being interwoven with both plies of wefts and each facing warp overlying one of the uniting warps.

4. The multi-ply woven felt as claimed in claim 1 and having three plies of filling wefts extending transversely of the felt, the wefts of the top and bottom plies being located one above the other and those of the intermediate ply being located midway between the wefts and of their intervals of the top and bottom ply and a plurality of warp strands extending longitudinally of the felt having a ratio of two facing warps to four back warps, two of the back warps being companion back warps to the facing warps, the two facing warps extending alternately downwardly from the top of the felt and under alternate intermediate wefts and upwardly and over two top ply wefts, the two companion warps underlying the two top wefts and the other two back warps being interwoven between the bottom and intermediate plies and positioned one between each facing warp and its companion warp.

5. The multi-ply woven felt as claimed in claim 1 and having two plies of filling wefts running transversely of the felt and located one above the other in a plane normal to the face of the felt, a plurality of warps extending longitudinally of the felt in the ratio of three facing warps to three back warps for each set, the facing warps extending successively under every third weft and over two successive wefts in the top ply, the back warps extending successively under every corresponding third weft in the bottom ply and over the same two upper wefts as covered by the facing warps, and underlying the facing warps throughout their length.

6. The multi-ply woven felt as claimed in claim 1 and having two plies of equally spaced filling wefts running transversely of the felt located one above the other, the wefts of the upper ply being above the intervals between the wefts in the lower ply, comprising a weave pattern of three facing warps and three underlying companion warps, the facing warps extending successively under every third and over the next two wefts of the top ply wefts, the three companion warps underlying the three facing warps and extending successively over only one of every three of the wefts traversed by the facing warps in the top ply of wefts and under every third weft in the bottom ply of wefts.

7. The multi-ply woven felt as claimed in claim 1 and having two plies of filling wefts running transversely of the felt located one above the other, in a plane normal to the face of the felt, a weave pattern of a set of six warps extending longitudinally of the felt one half of which are facing warps adapted to be woven along the top surface of the felt, and extending under every third weft in succession in the top ply of wefts, the remaining three warps underlying the three facing warps and extending successively over every third weft in the top ply and under the next two wefts in the bottom ply in succession.

' References Cited in the file of this patent UNITED STATES PATENTS 142,681 Dornan Sept. 9, 1873 648,567 Keefer May 1, 1900 684,980 Dornan Oct. 22, 1901 1,050,406 Veit Jan. 14, 1913 2,260,940 Hall Oct. 28, 1941 I FOREIGN PATENTS 731,243 Germany Feb. 4, 1943 

